HAL Id: inria-00072777
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Submitted on 24 May 2006
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Sparse Linear Algebra and Geophysical Migration
Yann-Hervé de Roeck
To cite this version:
Yann-Hervé de Roeck. Sparse Linear Algebra and Geophysical Migration. [Research Report] RR-3876,
INRIA. 2000. �inria-00072777�
ISRN INRIA/RR--3876--FR+ENG
a p p o r t
d e r e c h e r c h e
INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE
Sparse linear algebra and geophysical migration
Yann-Hervé De Roeck
N˚3876
Février 2000
THÈME 4
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steps in x # grid steps in z
24 50 100 95 101
3 953 780
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988 294 432
0,15%
Idem,
convolved 3 859 224 169 242 Idem, no
null column Idem, convolved
Dirac synthetics
Idem, no null column
8 286 76 817
8 286
# nonzeros in B % sparsity Dirac
synthetics 120 000 9 595
1 920 000
93 345 76 817
comments
Real high
res., Dirac 3 859 224 169 242
# rows of B # columns of B
1 920 000
93 219 Idem,
convolved 1 920 000 93 219 Problem
id.
1 1' 1"
3' 2 2' 2"
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Initial reflecttivity
Horizontal extent of the grid (m)
Vertical extent of the grid (m)
10 20 30 40 50 60 70 80 90
10
20
30
40
50
60
70
80
90
100
Initial reflectivity projected on the orthonal of Ker(B)
Horizontal extent of the grid (m)
Vertical extent of the grid (m)
10 20 30 40 50 60 70 80 90
10
20
30
40
50
60
70
80
90
100
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